Bones form the framework of our body. They support us, allow movement with the help of muscles, and protect vital organs by enclosing them in cavities, such as the brain in the skull, the spinal cord in the vertebral column, and the lungs and heart in the chest. To perform this role, bones are hard and rigid.
Bones, however, are not static tissue, nor do they have a constant density throughout our lives. They are “living” tissue that is continuously renewed. In bones, there is constant deposition of minerals—mainly calcium—by cells called osteoblasts, and at the same time removal of calcium by other cells called osteoclasts. This creates a balance between calcium deposition and removal. Every 3–5 years, our skeleton is fully renewed.
This calcium metabolism, and which side of the balance dominates, determines whether bone strength is sufficient to protect us from spontaneous fractures—fractures that can occur very easily without significant mechanical stress—as seen in osteoporosis.
Regarding bone metabolism, during childhood more calcium is added to bones than removed, gradually increasing bone density. At the same time, bone size increases. During adolescence, this increase continues until the ages of 25–35, when peak bone mass is reached. At this stage of life, bone mass stabilizes at its highest levels.
After this age, the opposite process begins. Bone breakdown and calcium loss exceed calcium deposition. This occurs in both men and women, but in women the rate of bone loss is much higher. As a result, the risk of osteoporosis is significantly greater in women.
Out of 100 people with osteoporosis, 90 are women and only 10 are men. It is also estimated that one in three women over the age of 50 and one in twenty men will develop osteoporosis. The reason for this difference is that estrogen—the female hormone that plays a major role in bone metabolism—declines sharply during menopause.
Seventy-five percent of fractures in people over the age of 45 are attributed to osteoporosis, a very high percentage. According to the World Health Organization, fractures due to osteoporosis are expected to quadruple over the next 50 years.
Before menopause, women naturally lose about 1% of their bone mass per year. Immediately afterward, for the next 5–10 years, bone loss increases to 3–6% per year. Later in life, the rate of loss decreases to about 2% per year.
Therefore, the greater the bone mass achieved during the 20s and 30s, the larger the bone reserves later in life and the lower the risk of developing osteoporosis. Proper nutrition, physical activity, and lifestyle habits that support bone mass at a young age play a major role here.
Predisposing Factors for Osteoporosis
Family history and genetic predisposition: The presence of osteoporosis in close relatives suggests a genetic predisposition. Identified genes include:
Genes of the vitamin D receptor (dysfunction leads to poor calcium absorption and deposition in bones).
Genes related to estrogen function.
Genes associated with osteoclast activity and calcitonin receptors (impaired calcium binding and removal).
Genes related to collagen synthesis in bones (dysfunction predisposes to osteoporosis).
- Female sex: Higher prevalence in women than men.
- Advanced age: Higher risk in older individuals.
- White race: More susceptible than darker-skinned populations.
- Small body frame or low body mass index (BMI <18).
- Early menopause or menstrual cycle disorders.
- Smoking and alcohol consumption.
- Sedentary lifestyle and limited physical activity.
- Excessive consumption of animal protein and inadequate calcium intake in relation to phosphorus and other minerals such as magnesium and boron.
- Insufficient exposure to sunlight: Daily exposure of 20–30 minutes is needed to synthesize vitamin D, which is essential for calcium metabolism.
- Gut microbiome: Increasing evidence shows that gut microbiota composition affects bone health. Recent research published in Frontiers in Endocrinology links specific bacteria—Akkermansia and DTU089—to poorer bone health in older adults. Akkermansia has been associated with obesity risk, while DTU089 levels are higher in sedentary individuals with low protein intake.
- Medications: Such as long-term corticosteroid use.
- Other medical conditions: Hypogonadism, thyroid disorders, kidney disease, rheumatic diseases, asthma, eating disorders, and others that impair peak bone density.
Symptoms
Osteoporosis is a silent disease and often provides no warning signs. About half of women with osteoporosis have no symptoms. Symptoms usually appear only in advanced stages, which makes preventive screening essential, especially for women around menopause.
Possible symptoms include back and spinal pain, pain in the arms and legs, fractures of long bones or vertebrae, loss of height, and kyphosis.
The Mysteries of Calcium
There are regions of the world where calcium intake is very low, yet osteoporosis is less common. For example, Bantu women in rural South Africa consume only 220–440 mg of calcium daily and rarely develop osteoporosis. In contrast, urban Bantu women consume two to four times more calcium but have thinner bones.
Why the difference? Rural Bantu women are primarily vegetarian, while urban women consume more meat. Animal protein increases urine acidity, which promotes calcium loss. Urban diets also tend to include more refined foods, sugar, and salt.
High protein intake increases urinary calcium excretion and osteoporosis risk, while very low protein intake also increases risk. Vegetarian diets appear to reduce osteoporosis risk. Bone mass in vegetarians and meat-eaters is similar until the age of 50, but after that, vegetarians experience slower bone loss.
Clinical studies show that calcium supplements can reduce bone calcium loss. However, evidence does not consistently support protection from fractures through high dairy intake. The Nurses’ Health Study involving 77,761 women found that increased milk consumption did not reduce fracture risk. Women who drank two or more glasses of milk per day had a 45% higher risk of hip fracture compared to those who drank one glass or less per week.
Stopping the “Calcium Thieves”
Excess sugar intake contributes to calcium loss from bones. Smoking, coffee, and alcohol disrupt estrogen metabolism and accelerate bone loss. Balanced nutrition rich in minerals and vitamins is essential for bone health, supporting both prevention and treatment.
Foods rich in calcium include green leafy vegetables, nuts, sesame seeds, cabbage, broccoli, kale, lettuce, legumes, whole grains, and beans. Small amounts of organic dairy products such as yogurt and full-fat cheese can be included occasionally. Daily calcium needs range from 800–1,000 mg and may increase to 1,500 mg in high-risk individuals.
Vitamin D is essential for calcium absorption and is obtained from sunlight and foods such as eggs and fortified cereals. Phosphorus, magnesium, boron, zinc, manganese, copper, silicon, strontium, and vanadium all contribute to bone strength and metabolism.
Vitamins for Healthy Bones and Teeth
Vitamin D enables calcium absorption. Vitamin K helps bind calcium to bones via osteocalcin. Vitamins B6, B12, folic acid, A, and C support bone metabolism and connective tissue health.
Exercise and Stress
Physical activity strengthens bones. Weight-bearing exercises such as walking, jogging, stair climbing, and even 20–30 minutes of daily walking help build bone density. Exercise also supports mental health and family well-being.
Chronic stress weakens the immune system and may contribute to dental decay. Managing stress supports overall skeletal and dental health.
Dental Care and Bone Health
Some toothpastes contain sodium lauryl sulfate (SLS), which may irritate oral tissues. Choosing SLS-free toothpaste and maintaining good oral hygiene can support dental and bone health.
Brush your teeth at least twice daily and use dental floss regularly.
Matina Chronopoulou
Naturopath